So you’ve jumped on the Sass bandwagon, and are tackling the intricacies of responsive web design. This session will show you the Sass tools that will help you shave hours off your responsive theme-building life. We’ll cover native Sass functions, useful and robust Sass libraries, and how to use these tools with the latest CSS features such as flexbox. This talk was first given at CSS Dev Conf 2014, but will be updated with the latest information.